Spatial resolution is typically obtained in x-ray transmission images either by means of a segmented detector, where pixels are illuminated in parallel by means of a fan- or cone-shaped x-ray beam, or else by means of a pencil beam that is scanned across an inspected object in a raster fashion. In some applications, transmission images are still obtained by exposure of an x-ray sensitive film. Segmented detectors are costly, whereas the mechanical structure required for collimating and scanning a pencil beam is not only costly but also heavy and cumbersome.